Bip39 offline https://atavi.com/share/xbwf7vz16jgof Although it employs BIP32 process you could still import BIP39 seeds into Electrum wallet. Also other than BIp32 There is certainly BIP44 Variation which some wallet use for your generation of seeds. Such as, when you at first create your wallet and created seed working with Ledger https://linktr.ee/bip39